Retrospective Study of the Effects of Zoledronic Acid on Muscle Mass in Osteoporosis Patients

Methodological guidance for the use of real-world data to measure exposure and utilization patterns of osteoporosis medications

Observational studies of osteoporosis medications can provide critical real-world evidence (RWE) that fills knowledge gaps left by clinical trials. However, careful consideration of study design is needed to yield reliable estimates of association. In particular, obtaining valid measurements of exposure to osteoporosis medications from real-world data (RWD) sources is complicated due to different medication classes, formulations, and routes of administration, each with different pharmacology. Extended half-lives of bisphosphonates and extended dosing of denosumab and zoledronic acid require particular attention. In addition, prescribing patterns and medication taking behavior often result in gaps in therapy, switching, and concomitant use of osteoporosis therapies. In this review, we present important considerations and provide specialized guidance for measuring osteoporosis drug exposures in RWD. First, we compare different sources of RWD used for osteoporosis drug studies and provide guidance on identifying osteoporosis medication use in these data sources. Next, we provide an overview of osteoporosis pharmacology and how it can influence decisions on exposure measurement within RWD. Finally, we present considerations for the measurement of osteoporosis medication exposure, adherence, switching, long-term exposures, and drug holidays using RWD. Ultimately, a thorough understanding of the differences in RWD sources and the pharmacology of osteoporosis medications is essential to obtain valid estimates of the relationship between osteoporosis medications and outcomes, such as fractures, but also to improve the critical appraisal of published studies.

Obesity - Standards, trends and advances

Obesity continues to be a significant global health concern, giving rise to various complications. This review article explores the current standards and emerging innovations in diagnosing and treating obesity, including recent disease name change, staging system or therapeutic goals. This narrative review has been based on recent scientific articles from PubMed database, limiting the scope of topics to current standards and upcoming developments and breakthroughs in the diagnosis and treatment of obesity. The educational and informative nature of the review has been maintained in order to make the information presented accessible to both researchers and clinical practitioners. The recognition of diverse obesity phenotypes has prompted a paradigm shift towards a complex and patient-centered approach to diagnosis and therapy. Pharmacotherapy for obesity is evolving rapidly, with ongoing research focusing on novel molecular targets and metabolic pathways. Promising developments include dual or triple incretin analogs, oral incretin drugs, neurotransmitter-based therapies, muscle mass-increasing treatments, and therapies targeting visceral adipose tissue browning. Despite current evidence-based international standards, the field of obesity diagnosis and treatment continues to expand, with new diagnostic tools and pharmacotherapies potentially replacing current practices. Therapeutic management should be tailored to individual patients, considering obesity phenotype, health status, lifestyle, and preferences. Looking ahead, the future holds promising opportunities for obesity management, but further research is required to assess the efficacy and safety of emerging therapies. A multifactorial and personalized approach will be pivotal in addressing the diverse challenges posed by obesity.

Bisphosphonates attenuate age-related muscle decline in Caenorhabditis elegans

BACKGROUND

Age-related muscle decline (sarcopenia) associates with numerous health risk factors and poor quality of life. Drugs that counter sarcopenia without harmful side effects are lacking, and repurposing existing pharmaceuticals could expedite realistic clinical options. Recent studies suggest bisphosphonates promote muscle health; however, the efficacy of bisphosphonates as an anti-sarcopenic therapy is currently unclear.

METHODS

Using Caenorhabditis elegans as a sarcopenia model, we treated animals with 100 nM, 1, 10, 100 and 500 μM zoledronic acid (ZA) and assessed lifespan and healthspan (movement rates) using a microfluidic chip device. The effects of ZA on sarcopenia were examined using GFP-tagged myofibres or mitochondria at days 0, 4 and 6 post-adulthood. Mechanisms of ZA-mediated healthspan extension were determined using combined ZA and targeted RNAi gene knockdown across the life-course.

RESULTS

We found 100 nM and 1 μM ZA increased lifespan (P < 0.001) and healthspan [954 ± 53 (100 nM) and 963 ± 48 (1 μM) vs. 834 ± 59% (untreated) population activity AUC, P < 0.05]. 10 μM ZA shortened lifespan (P < 0.0001) but not healthspan (758.9 ± 37 vs. 834 ± 59, P > 0.05), whereas 100 and 500 μM ZA were larval lethal. ZA (1 μM) significantly improved myofibrillar structure on days 4 and 6 post-adulthood (83 and 71% well-organized myofibres, respectively, vs. 56 and 34% controls, P < 0.0001) and increased well-networked mitochondria at day 6 (47 vs. 16% in controls, P < 0.01). Genes required for ZA-mediated healthspan extension included fdps-1/FDPS-1 (278 ± 9 vs. 894 ± 17% population activity AUC in knockdown + 1 μM ZA vs. untreated controls, respectively, P < 0.0001), daf-16/FOXO (680 ± 16 vs. 894 ± 17%, P < 0.01) and agxt-2/BAIBA (531 ± 23 vs. 552 ± 8%, P > 0.05). Life/healthspan was extended through knockdown of igdb-1/FNDC5 (635 ± 10 vs. 523 ± 10% population activity AUC in gene knockdown vs. untreated controls, P < 0.01) and sir-2.3/SIRT-4 (586 ± 10 vs. 523 ± 10%, P < 0.05), with no synergistic improvements in ZA co-treatment vs. knockdown alone [651 ± 12 vs. 635 ± 10% (igdb-1/FNDC5) and 583 ± 9 vs. 586 ± 10% (sir-2.3/SIRT-4), both P > 0.05]. Conversely, let-756/FGF21 and sir-2.2/SIRT-4 were dispensable for ZA-induced healthspan [630 ± 6 vs. 523 ± 10% population activity AUC in knockdown + 1 μM ZA vs. untreated controls, P < 0.01 (let-756/FGF21) and 568 ± 9 vs. 523 ± 10%, P < 0.05 (sir-2.2/SIRT-4)].

CONCLUSIONS

Despite lacking an endoskeleton, ZA delays Caenorhabditis elegans sarcopenia, which translates to improved neuromuscular function across the life course. Bisphosphonates might, therefore, be an immediately exploitable anti-sarcopenia therapy.

Strategies to reduce the onset of sleeve gastrectomy associated bone loss (STRONG BONES): Trial design and methods

Background

Despite recognized improvements in obesity-related comorbidities, mounting evidence implicates surgical weight loss in the onset of skeletal fragility. Sleeve gastrectomy (SG) is the most commonly performed bariatric procedure and is associated with 3-7% axial bone loss in the year following surgery. Bisphosphonates are FDA-approved medications for the prevention and treatment of age-related bone loss and may represent a strategy to reduce bone loss following SG surgery.

Methods

The Strategies to Reduce the Onset of Sleeve Gastrectomy Associated Bone Loss (STRONG BONES) trial (NCT04922333) is designed to definitively test whether monthly administration of the bisphosphonate, risedronate, for six months can effectively counter SG-associated bone loss. Approximately 120 middle-aged and older (≥40 years) SG patients will be randomized to six months of risedronate or placebo treatment, with skeletal outcomes assessed at baseline, six, and 12-months post-surgery. The primary outcome of the trial is 12-month change in total hip areal bone mineral density (aBMD), measured by dual energy x-ray absorptiometry (DXA). This will be complemented by DXA-acquired aBMD assessment at other skeletal sites and quantitative computed tomography (QCT) derived changes in bone quality. Change in muscle mass and function will also be assessed, as well as biomarkers of bone health, turnover, and crosstalk, providing mechanistic insight into intervention-related changes to the bone-muscle unit.

Discussion

Results from the STRONG BONES trial have the potential to influence current clinical practice by determining the ability of bisphosphonate use to mitigate bone loss and concomitant fracture risk in middle-aged and older SG patients.

Sarcopenia, osteoporosis and frailty

Muscles and bones are intricately connected tissues displaying marked co-variation during development, growth, aging, and in many diseases. While the diagnosis and treatment of osteoporosis are well established in clinical practice, sarcopenia has only been classified internationally as a disease in 2016. Both conditions are associated with an increased risk of adverse health outcomes such as fractures, dysmobility and mortality. Rather than focusing on one dimension of bone or muscle mass or weakness, the concept of musculoskeletal frailty captures the overall loss of physiological reserves in the locomotor system with age. The term osteosarcopenia in particular refers to the double jeopardy of osteoporosis and sarcopenia. Muscle-bone interactions at the biomechanical, cellular, paracrine, endocrine, neuronal or nutritional level may contribute to the pathophysiology of osteosarcopenia. The paradigm wherein muscle force controls bone strength is increasingly facing competition from a model centering on the exchange of myokines, osteokines and adipokines. The most promising results have been obtained in preclinical models where common drug targets have been identified to treat these conditions simultaneously. In this narrative review, we critically summarize the current understanding of the definitions, epidemiology, pathophysiology, and treatment of osteosarcopenia as part of an integrative approach to musculoskeletal frailty.

Osteosarcopenia and Pain: Do We Have a Way Out?

Osteosarcopenia (OSP) is a geriatric syndrome characterized by the coexistence of osteoporosis and sarcopenia and associated with an increased risk of fragility fractures, disability, and mortality. For patients with this syndrome, musculoskeletal pain represents the most significant challenge since, in addition to limiting the individual's functionality and promoting disability, it has a huge psychological burden involving anxiety, depression, and social withdrawal. Unfortunately, the molecular mechanisms involved in the development and persistence of pain in OSP have not yet been fully elucidated, although immune cells are known to play a key role in these processes. Indeed, they release several molecules that promote persistent inflammation and nociceptive stimulation, resulting in the gating of ion channels responsible for the generation and propagation of the noxious stimulus. The adoption of countermeasures to counteract the OSP progression and reduce the algic component appears to be necessary, providing patients with a better quality of life and greater adherence to treatment. In addition, the development of multimodal therapies, based on an interdisciplinary approach, appears to be crucial, combining the use of anti-osteoporotic drugs with an educational programme, regular physical activity, and proper nutrition to eliminate risk factors. Based on this evidence, we conducted a narrative review using the PubMed and Google Scholar search engines to summarize the current knowledge on the molecular mechanisms involved in the pain development in OSP and the potential countermeasures to be taken. The lack of studies addressing this topic highlights the need to conduct new research into the resolution of an ever-expanding social problem.

Zoledronate Reduces Height Loss Independently of Vertebral Fracture Occurrence in a Randomized Trial in Osteopenic Older Women

Vertebral fractures are associated with height loss, reduced quality of life, and increased mortality and are an important endpoint for osteoporosis trials. However, height loss is associated with quality of life and mortality independent of associations with fracture. We have used data from a recent 6-year trial of zoledronate in 2000 osteopenic women aged >65 years to assess the impact of the semiquantitative and quantitative components of the definition of vertebral fracture on the outcome of that trial, to determine what factors impacted on height loss and to test whether height loss can be used as a surrogate for vertebral fracture incidence. In the trial protocol, an incident vertebral fracture was defined as a change in Genant grade plus both a 20% and 4 mm decrease in a vertebral height. The addition of the quantitative criteria reduced the number of fractures detected but did not change the size of the anti-fracture effect (odds ratios of 0.49 versus 0.45) nor the width of the confidence intervals for the odds ratios. Multivariate analysis of baseline predictors of height change showed that age accelerated height loss (p < 0.0001) and zoledronate reduced it (p = 0.0001). Incident vertebral fracture increased height loss (p = 0.0005) but accounted for only 0.7% of the variance in height change, so fracture could not be reliably inferred from height loss. In women without incident vertebral fractures, height loss was still reduced by zoledronate (height change: zoledronate, -1.23; placebo -1.51 mm/yr, p < 0.0001). This likely indicates that zoledronate prevents a subtle but widespread loss of vertebral body heights not detected by vertebral morphometry. Because height loss is associated with quality of life and mortality independent of associations with fracture, it is possible that zoledronate impacts on these endpoints via its effects on vertebral body integrity. © 2022 American Society for Bone and Mineral Research (ASBMR).

Muscle-Specific Micro-Ribonucleic Acids miR-1-3p, miR-133a-3p, and miR-133b Reflect Muscle Regeneration After Single-Dose Zoledronic Acid Following Rotator Cuff Repair in a Rodent Chronic Defect Model

BACKGROUND

Zoledronic acid improves bone microarchitecture and biomechanical properties after chronic rotator cuff repair (RCR) in rats. Besides the positive effects of zoledronic acid on bone mineral density and bone microarchitecture, bisphosphonates have positive effects on skeletal muscle function.

PURPOSES/HYPOTHESIS

The purposes of this study were to (1) longitudinally evaluate circulating bone- and muscle-specific serum micro-ribonucleic acids (miRNAs) and (2) investigate supraspinatus muscle tissue after tenotomy and delayed RCR in a rat model. It was hypothesized that zoledronic acid would improve muscle regeneration after chronic RCR in rats.

STUDY DESIGN

Controlled laboratory study.

METHODS

A total of 34 male Sprague-Dawley rats underwent unilateral (left) supraspinatus tenotomy (time point 1) with delayed transosseous RCR after 3 weeks (time point 2). All rats were sacrificed 8 weeks after RCR (time point 3). Animals were randomly assigned to 2 groups. One day after RCR, the control group was given 1 mL of subcutaneous saline solution, and the intervention group was treated with a subcutaneous single-dose of 100 µg/kg body weight of zoledronic acid. All 34 study animals underwent miRNA analysis at all 3 time points. In 4 animals of each group, histological analyses as well as gene expression analyses were conducted.

RESULTS

Circulating miRNAs showed significantly different expressions between both study groups. In the control group, a significant downregulation was observed for muscle-specific miR-1-3p (P = .004), miR-133a-3p (P < .001), and miR-133b (P < .001). Histological analyses showed significantly higher rates of regenerating myofibers on the operated side (left) of both study groups compared with the nonoperated side (right; P = .002). On the nonoperated side, significantly higher rates of regenerating myofibers were observed in the intervention group compared with the control group (P = .031). The myofiber cross-sectional area revealed significantly smaller myofibers on both sides within the intervention group compared with both sides of the control group (P < .001). Within the intervention group, significantly higher expression levels of muscle development/regeneration marker genes embryonal Myosin heavy chain (P = .017) and neonatal Myosin heavy chain (P = .016) were observed on the nonoperated side compared with the operated side.

CONCLUSION

An adjuvant single-dose of zoledronic acid after RCR in a chronic defect model in rats led to significant differences in bone- and muscle-specific miRNA levels. Therefore, miR-1-3p, miR-133a-3p, and miR-133b might be used as biomarkers for muscle regeneration after RCR.

CLINICAL RELEVANCE

Adjuvant treatment with zoledronic acid may improve muscle regeneration after chronic RCR in humans, thus counteracting fatty muscle infiltration and atrophy.

Curative Effect of Prebiotics/Probiotics Preparations Combined with Zoledronic Acid + Calcitriol Regimen on Patients with Primary Osteoporosis and Their Influences on Bone Metabolism Markers

Objective

To explore the curative effect of prebiotics/probiotics preparations combined with zoledronic acid + calcitriol regimen on patients with primary osteoporosis (POP) and the influences of prebiotics/probiotics preparations combined with zoledronic acid + calcitriol regimen on markers of bone metabolism.

Methods

126 elderly hospitalized patients with POP in our hospital from January 2020 to December 2021 were divided into the control group (n = 63) and the observation group (n = 63) by the random number table method. The patients in the control group were treated with zoledronic acid and calcitriol, while the patients in the observation group were additionally treated with prebiotics/probiotics preparations. The clinical curative effect, bone metabolism, calcium-phosphorus metabolism indexes, intestinal floras, and cytokines levels before and via treatment between the two groups were compared.

Results

The total efficiency of the observation group was higher than that of the control group (P < 0.05). After treatment, the levels of bone gla protein (BGP), total propeptide of type I procollagen (PINP), and β-crosslaps (β-CTX) in both groups were lower than those before treatment, and the levels of BGP, total PINP, and β-CTX in the observation group were lower than those in the control group (P < 0.05). The levels of serum P in the both groups after treatment were lower than those before treatment, and the level of serum P in the observation group was lower than that in the control group (P < 0.05). The number of Escherichia coli after treatment in the two groups were less than that before treatment, and the number of Escherichia coli in the observation group was less than that in the control group (P < 0.05). The number of bifidobacteria and lactobacilli in the two groups after treatment were more than that before treatment, and the number of bifidobacteria and lactobacilli in the observation group were more than those in the control group (P < 0.05). After treatment, the levels of IL-6 and TNF-α in the two groups were lower than those before treatment, and the levels of IL-6 and TNF-α in the observation group was lower than those in the control group (P < 0.05). The levels of IGF-1 in the two groups after treatment were higher than those before treatment, and the levels of IGF-1 in the observation group was higher than that in the control group (P < 0.05).

Conclusion

The response rate of prebiotics/probiotics preparations combined with zoledronic acid + calcitriol regimen is high in the treatment of POP patients, which ameliorates bone metabolism and intestinal floras, and suppresses cytokines release in patients with POP.

Risedronate or Exercise for Lean Mass Preservation During Menopause: Secondary Analysis of a Randomized Controlled Trial

BACKGROUND

The menopause transition is marked by hormonal shifts leading to body composition changes, such as fat mass gain and lean mass loss. Weight-bearing and resistance exercise can help maintain lean mass during the menopause transition; however, uptake is low. Pre-clinical research points to bisphosphonates as also being effective in preventing loss of lean mass. Thus, we sought to investigate whether bisphosphonate therapy can mitigate loss of lean mass and outperform weight-bearing exercise in the years immediately following menopause.

METHODS

Data come from the Heartland Osteoporosis Prevention Study (NCT02186600), where osteopenic, postmenopausal women were randomized to bisphosphonate (n=91), weight-bearing/resistance exercise (n=92), or control (n=93) conditions over a one-year period. Dual energy X-ray absorptiometry (DXA)-derived body composition measures (including total lean mass, total fat mass, lean mass index, and lean mass-to-fat mass ratio) were ascertained at baseline, six, and 12-months. Adherence to risedronate and weight-bearing exercise was defined as the percentage of dosages taken and exercise sessions attended. Intent-to-treat analysis using linear modeling was used to generate treatment effects on body composition. Secondary analysis utilized per-protocol analysis and included adjustment for weight change.

RESULTS

276 women (age: 54.5 years; 83.3% Caucasian; BMI: 25.7 kg/m²) were included in the analyses. 12-month adherence to the risedronate and exercise interventions was 89% and 64%, respectively. Group-by-time interactions were observed for lean mass, revealing exercise (0.43±1.49kg) and risedronate groups (0.31±1.68 kg) gained significantly more lean mass than control (-0.15±1.27 kg) over 12-months. However, after controlling for weight change in secondary analysis, the difference in lean mass change between control and risedronate became non-significant (p=0.059).

CONCLUSIONS

Results suggest both 12 months of oral risedronate and 12 months of weight-bearing exercise may diminish lean mass loss experienced during the menopause transition as compared to control. The lean mass sparing effect for risedronate may be driven by overall weight change.

Does Zoledronic Acid Improve Appendicular Lean Mass in Older Women with Osteoporosis? A Sub-Analysis of a Randomized Clinical Trial

BACKGROUND

Coexistence of osteoporosis and sarcopenia (osteosarcopenia), is associated with increased risk for fractures, falls, and mortality. Although there are multiple medications for management of osteoporosis, there are no approved pharmacotherapy for sarcopenia.

OBJECTIVES

We examined the effect of zoledronic acid on muscle mass indices including ALM (Appendicular Lean Mass) and ALM/Height2 in a cohort of older women with osteoporosis who were residents of Long-Term Care Communities (LTCCs).

DESIGN

A secondary analysis of a 2-year double-blind, randomized, placebo-controlled clinical trial.

SETTING

Residents of LTCCs.

PARTICIPANTS

Sixty-two postmenopausal women with osteoporosis.

INTERVENTION

Participants either received 5 mg infusion of zoledronic acid or placebo, once at the start of the study.

MEASUREMENTS

Participant's ALM/Height2, ALM, total hip BMD (Bone Mineral Density) and spine BMD were measured in 6, 12 and 24 months.

RESULTS

On average, participants were 86.7 years old and had a BMI of 27.4 kg/m2. There was no significant difference in change from baseline (mean ± SE) between the treatment group and the placebo group in ALM/Height2: (-0.15 vs -0.02, p = 0.541) and (-0.17 vs 0.001, p = 0.315) and (-0.29 vs -0.19, p = 0.646) or ALM: (-0.38 vs -0.09, p = 0.455) and (-0.45 vs -0.005, p = 0.216) and (-0.70 vs -0.48, p = 0.553) at 6, 12, and 24 months respectively. In addition, after adjusting for a possible confounding, the ALM/Height2 or ALM did not have significant improvements from baseline at 6 months, 12 months, and 24 months either in the treatment group or in the placebo group. However, there were significant improvements in the BMD at the total hip and the spine in the treatment group compared with the placebo group at all three time points.

CONCLUSIONS

Among older women residing in LTCCs, a single dose of zoledronic acid did not increase ALM/Height2 and ALM, despite improving the BMD at the total hip and the spine at the 2-year follow-up.